Influence of Electronic Structure on the Magnetic Properties of IV-VI Diluted Magnetic Semiconductors
Abstract
We investigated the magnetic and thermal properties of chalcogenide-based diluted magnetic semiconductor (DMS) systems. These systems have been considered as possible novel materials with increased magnetic sensitivity and thermoelectric efficiency. Measurements of the magnetic properties of Sn(1-x)Gd(x)Te show that there is an antiferromagnetic pair-exchange interaction with a maximum in the magnitude at a hole concentration of about 3 x 10(exp 20) /cu cm. The interpretation of this result is based on the relative positions of the Gd 5d level, the Fermi level, and the L and sum sigma levels in the valence band. We have also measured the low-temperature specific heat in these DMS systems. Theoretical calculations have shown that one must take into account the systems of magnetic ions and the carriers and the interactions between them in order to obtain an approximate fit to the data. We have performed measurements of the thermoelectric power, thermoelectric figure of merit, and electrical conductivity in P(1-x)Mn(x)Te. The thermoelectric power increased as the Mn-content increased, but a decrease in the carrier mobility limited the thermoelectric figure of merit. In new quaternary and pentenary DMS we have observed a paramagnet - ferromagnet transition and a temperature dependent anomalous Hall effect.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2001
- Accession Number
- ADA396782
Entities
People
- Malgorzata Gorska
Organizations
- Polish Academy of Sciences